This invention relates to a self-priming injection site. More particularly, this invention relates to a combination injection site and check valve for use in a parenteral solution administration apparatus whereby the apparatus is constructed so that the fluid flowing through the check valve automatically primes the injection site.
Presently, injection sites are generally `Y` shaped with one of the top arms of the `Y` being covered by a sleeve stopper formed of a latex compound. The sleeve stopper known in the prior art surrounds both the inside and the outside of the upper portion of the hollow arm. The sleeve stopper has a center that extends across the hollow arm of the injection site to prevent contaminants from entering the intravenous administration set. The closed center surface is generally located adjacent to the end of the hollow arm. To add medication or other solutions to the fluids already passing through the administration set, medical personnel use a syringe or other injection apparatus to pierce through the center surface of the sleeve stopper. Upon the needle being inserted into and removed from the sleeve stopper, the sleeve stopper may be damaged, rearranged, or even removed from the injection site. The sleeve-type stopper is particularly susceptible to being pulled from the injection site by large gauge needles since the sleeve-type stopper depends solely on the friction between itself and the arm of the injection site to retain the stopper in proper position. Since the friction alone is often insufficient, a vinyl heat seal band may be placed around the outside of the sleeve stopper and the adjacent portion of the arm. Although the heat seal band has improved the retention of the stopper in the arm, the results have still not been totally satisfactory.
The stoppers are generally formed of latex or a similar material that substantially reseals upon the needle being removed. However, repeated piercings damage the stopper, especially piercings done in such a manner that they create substantially larger openings. Once the stopper has been damaged by piercing, the stopper develops an even greater propensity to being moved from its proper position.
The removal of the stopper from the injection site causes an assortment of problems including fluids leaking from the administration set and the introduction of contaminants and air into the intravenous solution. The problem of stoppers that do not remain in their proper position on the injection site is particularly troublesome since the injection site is not independently removable from the administration set. The entire administration set must be changed to allow a new injection site to be put into place. It would be an advantage to provide an injection site which can withstand a large number of needle piercings and removals even when subjected to high pressures often associated with injections from small syringes, which may exceed 125 p.s.i.
It is an object of this invention to provide an improved injection site which can withstand a number of needle piercings and removals without the stopper being repositioned or removed from the injection site.
It is a further object of this invention to provide an injection site that is self-priming or easily primed.
One additional object of this invention is to provide minimal amounts of internal residual volume within the injection site lumen.